Part Number: KT1438
Ilmor KT1438 Thermostat Kit
Keep your marine engine running at the proper operating temperature with the Ilmor KT1438 Thermostat Kit. Designed as a genuine OEM replacement, this complete thermostat service kit helps regulate coolant flow and maintain consistent cooling system performance under demanding marine conditions.
The thermostat is a critical component in the engine cooling system, controlling when coolant circulates through the engine block. A worn or sticking thermostat can lead to overheating, unstable temperature readings, poor fuel efficiency, or slow engine warm-up. Replacing the thermostat and related sealing components helps restore proper coolant circulation and dependable engine performance.
Built to Ilmor factory specifications, the KT1438 thermostat kit is engineered for long-term durability in high-performance marine applications. Designed as a direct-fit service replacement, it provides reliable cooling system operation and straightforward installation for compatible Ilmor engines.
Common Engine Fitments
The Ilmor KT1438 thermostat kit is commonly used on Ilmor MV8 and GDI marine engines, including:
- Ilmor MV8 5.7L
- Ilmor MV8 6.0L
- Ilmor MV8 6.2L
- Ilmor 5700GDI
- Ilmor 6000GDI
- Ilmor 6.2L GDI and GDI-S engine platforms
These engines are widely found in premium towboats and surf boats, including:
- MasterCraft X22
- MasterCraft X24
- MasterCraft X26
- MasterCraft XT21, XT22, and XT23
- MasterCraft NXT22 and NXT24
- MasterCraft ProStar
These boats frequently operate under heavy ballast loads and extended surf sessions, making stable cooling system performance essential for engine reliability and consistent operation.
Fitment can vary depending on engine serial number and cooling system configuration, so confirming compatibility with part number KT1438 before ordering is recommended.
Typical Kit Contents
Depending on production revision, the kit may include:
- Marine thermostat
- Thermostat housing gasket or seal
- O-rings and sealing components
- Related installation hardware
Contents may vary slightly by production batch.
Key Features
- Genuine Ilmor OEM thermostat kit
- Maintains proper engine operating temperature
- Helps restore reliable coolant circulation and cooling performance
- Designed for MV8 and GDI marine engines
- Marine-grade components built for durability
- Direct-fit replacement for easy installation
Why Replace a Thermostat Kit?
Over time, thermostats can wear out or stick due to repeated heat cycles and coolant exposure. Replacing the thermostat and seals together helps maintain proper cooling system pressure, stabilize engine temperatures, and reduce the risk of overheating-related engine damage.
If you’re servicing an Ilmor-powered MasterCraft, the KT1438 thermostat kit delivers the OEM-quality fit and dependable cooling performance your engine was designed for.